Hi Crzygrl, welcome to SI!
Good job on telling your BH. I didn't, I had to get caught because I was not brave enough to end my As myself or come clean on my own.
I understand your frustration. I wasn't happy and I was angry at my H in my M, so I cheated. That was a terrible reason. I didn't go to him, we had both become complacent but it was like we were in two different marriages. He really didn't know how I was feeling.
Anyway, back to you ...your M issues and your ONS are two different things. You chose to cheat. Why? What allowed you to give yourself permission to do this? (You don't have to answer me, just food for thought)
I definitely think you need IC.
what else I can say to convince him I am the same girl he loved before.
You're really not the same girl he loved before, but that's okay. Life is fluid, we are fluid, changes in us happen. The key is getting to the root of it.
You have a lot of digging to do.
To answer your questions...you are allowed to express your emotions (you should, not doing that is what led you here!), but you also have to remember how deep and devastating your BH's pain is. You'll need to communicate well, have 100% transparency with him, and not get annoyed or impatient when he asks questions or is having a terrible day.
This is a lot...a lot for you to process, and you are at the beginning of your journey. Keep posting. I know you will find the support that you need here.